# SDR SWAA2025071690761

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 12, 2025
- Submitted: July 16, 2025
- Operation: Air carrier
- Aircraft: [N8813Q](https://openairdocs.org/aircraft/N8813Q), registered now
- Make and model: Boeing 737-8
- Registry model: [Boeing 737-8](https://openairdocs.org/model/boeing-737-8) (OpenAirDocs)
- Aircraft serial: 42646
- Aircraft time: 13,771 hours, 7,522 cycles
- System (JASC): [4900 · Airborne Auxiliary Power Unit (APU) System](https://openairdocs.org/jasc/4900)
- Part: Apu
- Condition: Tripped
- Location: Zone 100
- Stage of operation: TX
- How discovered: O
- Nature of condition: B, J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/SWAA2025071690761

## Discrepancy

JUST PRIOR TO BRAKE RELEASE; APU TRIPPED OFFLINE AND GOT A STRONG ACIDIC SMELL IN THE FLT DECK AND THROUGHOUT THE ENTIRE AIRCRAFT.   OK TO CONTINUE 49-11-01 SP 1 AND SP 2.  P6-4 APU CONT COLLARD P6-5 INLET DOOR COLLARD.  APU OPS CHECKS OK. NO HISTORY. RAN APU FOR 30 MINUTES; NO DEFECTS NOTED; NO ABNORMAL SMELLS. REFERENCE M/M 49-11-00.

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